The present disclosure relates to electromagnetic propulsion systems, and more particularly to propulsion systems having wireless power transfer systems.
Electromagnetic propulsion systems operate to move a first structure relative to a stationary second structure generally through magnetic levitation. Without tethers, it is difficult to provide on-board power to the moving first structure.
Self-propelled elevator systems, as one non-limiting example, may utilize such magnetic propulsion systems. Such ropeless elevator systems are useful in certain applications (e.g., high rise buildings) where the mass of the ropes for a roped system is prohibitive and/or there is a need for multiple elevator cars in a single hoistway. Elevator cars typically need power for ventilation, lighting systems, operation of doors and brakes, control units, communication units and to recharge batteries installed, for example, on an elevator car controller. Moreover, elevator cars may require back-up systems in case of a power failure. Existing systems use moving cables or current collectors/sliders to connect a moving elevator car with power lines distributed along the elevator hoistway.